What 󠆜 means
The exact character-selector pair chooses the shape.
A variation selector follows its base character. The Unicode Ideographic Variation Database (IVD) registers supported pairs and maps each to acceptable glyphs—the shapes a font draws for that character. The same selector can request different forms after different characters, so its number alone is not a shape code.
Variation selectors let plain text preserve distinctions in written form without encoding each form as a separate character. The IVD's first collection, Adobe-Japan1, entered the registry on 2007-12-14.
Why does VS173 look blank?
It has no standalone visible form.
If an application lacks support for the pair, it normally leaves the base character in its usual form and does not display the selector. A text editor's show-hidden view may reveal it. Unicode's rules say unregistered ideographic sequences should not be used for text interchange.
A typography instruction whose effect depends on the exact ideograph-selector pair.
Don't attach it at random: only registered pairs define forms for text interchange.
Don't confuse it with
4Questions people ask
1Why does 󠆜 show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type 󠆜
󠆜\E019CCodes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.